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Inventory, net (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Disclosure of inventory net [Line Items]      
Finished goods $ 7,715 $ 6,151 $ 0
Products in process [1] 73,796 56,190  
Spare parts and supplies 81,383 84,787  
Inventory gross 162,894 147,128  
Provision for impairment of value of inventory [2] (23,163) (11,603)  
Finished goods [Abstract]      
Current inventories 135,919 132,287  
Inventories, net 3,812 3,238  
Inventories 139,731 135,525  
Minera Yanacocha SRL and subsidiary [Member]      
Disclosure of inventory net [Line Items]      
Inventory gross 62,042 77,722  
Allowance for obsolescence of materials and supplies (7,515) (7,076)  
Finished goods [Abstract]      
Inventories 54,527 70,646  
Minera Yanacocha SRL and subsidiary [Member] | Precious metals [Member]      
Disclosure of inventory net [Line Items]      
Inventory gross 6,878 15,446  
Minera Yanacocha SRL and subsidiary [Member] | Leach in circuit [Member]      
Disclosure of inventory net [Line Items]      
Inventory gross 1,835 8,057  
Minera Yanacocha SRL and subsidiary [Member] | Mill in circuit [Member]      
Disclosure of inventory net [Line Items]      
Inventory gross 4,002 2,048  
Minera Yanacocha SRL and subsidiary [Member] | Materials and supplies [Member]      
Disclosure of inventory net [Line Items]      
Inventory gross 49,327 52,171  
Sociedad Minera Cerro Verde S.A.A. [Member]      
Disclosure of inventory net [Line Items]      
Products in process [3] 149,975 148,928  
Finished goods [Abstract]      
Copper cathode 8,035 4,032  
Copper concentrate 17,949 18,068  
Molybdenum concentrate 3,205 1,896  
Less: Provision for obsolescence of materials and supplies (11) (1,237)  
Current inventories 487,531 445,626  
Inventories, net [3] 255,918 248,452  
Inventories 743,449 694,078  
Materials and supplies $ 308,378 $ 273,939  
[1] Products in process include mineral deposits located in the Tajo Norte mining unit (El Brocal). The detail of this mineral as of December 31, 2018 and 2017 is presented below:
[2] The provision for impairment of value of inventory had the following movement during the years 2018, 2017 and 2016:
[3] Work-in-process inventories represent mill and leach stockpiles, which contain higher grade ores (mill stockpiles) and medium and lower grade ores (leach stockpiles) that have been extracted from the open pit and are available for copper recovery. Based on the future mine plan production, the Company identifies the portion of inventory that is classified as current or long term. For mill stockpiles, recovery is through milling and concentrating. For leach stockpiles, recovery is through exposure to acidic solutions that dissolve copper and deliver it in a solution to extraction processing facilities.